W28 is a composite-type SNR that appears as a shell that is \({42} {}\)  in diameter in the radio continuum emission [1]}, [2]} and is located at \(l\)  = 6.4\({}\) , \(b\)  = –0.2\({}\)  in the Galactic plane (see Fig. REF ). It shows thermal X-Ray emission [3]} as well as gamma ray sources [4]}, [5]}, [6]}. Many CO studies [7]}, [8]}, [9]} show massive molecular clouds toward the north-east and the south of the SNR. Emission lines from these clouds were found to be mostly centered at a local standard of rest velocity, \(V_{\text{LSR}}\) ,
of \(\approx 7\,\rm km\,s^{-1}\) , which is consistent with values estimated from HI observations [10]}. The interaction of the SNR shock with the molecular cloud towards its east side appears to be responsible for the enhanced synchrotron and thermal X-ray emissions [2]}. Broad CO line widths (\(\Delta V\)  = 30–50 \({}\) ) were observed by [12]} along the gaseous ridges of the molecular cloud facing the shock front while the lines off the ridges were narrow. A very high energy (VHE) \(\gamma \) -ray emission source, HESS J1801-233 [4]}, is also coincident with the northeastern boundary of W28, providing further evidence of SNR-MC interactions.
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